Backrest for chair



FIG. 1 is a perspective view of the backrest for chair embodying the design of the invention and shown installed with the seat and legs of a representative chair being shown in phantom outline;

FIG. 2 is a top elevational view of the backrest;

FIG. 3 is a front elevational view of said backrest;

FIG. 4 is the side elevational view of said backrest, the opposite side being substantially the same in appearance;

FIG. 5 is the rear elevational view of said backrest; and,

FIG. 6 is a bottom plan view of said backrest. 

The ornamental design for a backrest for chair, as shown and described. 